Helicopter rotor



July 29, 1952 c. o. slPE 2,604,950

HELICOPTER RoToR Filed April 23, 1946 f W VA INVENTOR.

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Patented July 29, 1952 UNITED STATES PATENT'4 OFFICE l 2,604,950y I 1 H-EucoPTER Vltolfron I CharlesO. Sipe, Woody,'Cali`i'. Appuoaiionapril 23, 1946,. serial No'. '664.267

1` claim'. (ci. 17d- 16021)` l This invention relates to helicopters and more especially to the rotor utilized for attaining altitude.

The invention aims to provide a lifting rotor 'system' comprising concentric elements rotatable in oppositev directionsrespectively about av cornm'on axis, each `of said elements carrying one or .more blades so mounted-that when each element 'is revolving ina directiondesigned to lift the structure, it or they will be held in place by the resistance of the air in the path thereof but, when such resistance is removed, as by discontinuance off'operation of the wheel, the blade or blades will shift into positions Where they will so-operate with the rotatable elements to form a parachute structure, serving to retard theV descent of the structure. 1

The invention is hereinafter defined in the appended claim.

In the accompanying drawing the preferred embodiment of the invention is illustrated.

In said drawing:

Figure 1 is a top plan view of the rotor system, a portion being broken away;

y y Figure 2 is a section taken substantially on the line 2-2 of Figure 1. Y

Figure 3 is an edge view of a portion of the rotor taken in the direction of the arrow inA Figure 2.Y l

. Fig. 4 is a` fragmentary sectional View taken substantially on the line 4 4 of Fig. 1.

Referring to the iiguresby characters of refere'nceA designates the inner rotor member and B designates the cuter rotor member. The inner rotor member includes a hub I xedly connected to and rotatable with a vertical tubular shaft 2 and extending outwardly and downwardly from this hub I are regularly spaced, segmental, open frames 3 the outer end edges of which are concentric with the shaft and are in a common plane that is disposed perpendicularly to the shaft. Extending longitudinally of each of these frames close to and parallel with one side thereof is a shaft 4 on which a segmental blade 5 is pivotally mounted, this blade being so proportioned in length and width that, when swung on its shaft 4 to one eXtreme position, it moves substantially into the plane of, and substantially lls the space dened by, the frame in which it is mounted.

When swung on their shafts 4 to their other extreme positions, however, the blades are in their active positions as lifting mediums. In this connection, assuming that the helicopter is still, it will be seen that each blade 5 has its greatest planar with`r the'frames "andV whichv "can-be formed areaand weight disposed below its point ofv'plvotal 'mountngrepresefnted by shaft *'Therefore, thestill positionof the helicopter, the blades will tend to hang. straightdownwardly. If, now, the inner rotorA member A yis rotated 'in the direction of the arrows seenin the resistancev of the air yin the path of said .depeiidf ing blades will swing the blades. to the bladeprijsitions seen in Figs .'.-1'3. vIn these ppsitionspthe blades 5 are `inclined andtherefore, theair moving toward the left in `1=.ig.3,A i'mp'inges upongv'the right hand surface (in Fig. 3.) of the blaiie and streams downwardly and past. the lower fedg'e 'o'f said blade 5. 'The blade 5 thus actsasa lifting .medium in this extremefpositionseenin 3.

It win not move runner tothe leftin Fie. 'argom this inclined; positionbecause it is. 'engaged against doingso byrhat iongitudmn edge -o'f freme disposed pelose to end para'llel te ,the Shaft 4 von, whichthe blade' isvpivoted: (see Fig ll):4

`There is provided alongfthe upper edgeof ach blade a flap 6 disposed above-'.theLpiyot-aizm f the blade and Whiclfrs sqipstionedvthat" Wh i1 the blade is in activey posftion,` the apis'in lined with the part of `the bia-do. disposed"belowA yne pivot axis, as seen from FigLSS', ilapn'isjja means of givinglmore ain from above the plane ofthe rotor member A,ff or iinpngementagai t the blade 5.` :j j g 'i The spaces between thesegmentalfra are closed by meansfof "segmentall panels of thin sheet metal opposed converging edgesf'of which are seated in grooves 8 provided therefor in the sides of the segmental frames. In other words these thin panels can be inserted between the frames with which they will be securely assembled, thereby forming a rotor made up of panels and segmental frames successively arranged. Thus when the blades 5 swing to closed positions across their frames 3, they co-operate with the inserted panels 1 to form a substantially solid disc.

By reference to Fig. 3, it may be noted that in the lifting position of the blades 5, the blades are disposed at an acute angle to the panels 'I immediately adjacent thereto, and at an obtuse angle to the open frames 3 on which they are pivotally mounted.

A shaft 9 is rotatably mounted within the tubular shaft 2 and secured to the upper end thereof is a hub I0 forming a part of the outery rotor B. Arms I I radiate from this hub and are positioned above the inner rotor A. Downwardly extending terminals I2 are provided at the outer ends of the arms I I and extend to points close to but outside of the periphery of the rotor A and extending from each of these terminals is a segmental frame I3 supported beyond the periphery of the inner rotor.

A shaft I4 is journalled in each segmental frame I3 close to that side thereof remote from the advancing edge of the frame and each of these shafts, which is parallel with the adjacent side of the frame I3, has a depending blade I5 pivotally mounted thereon and extending normally below the frame. The blade is so shaped and proportioned that when it is in one extreme position it bears upwardly against its frame and substantially closes it. A flap IB is provided along the upper edge of the blade and is an airgathering means similar to flap 6. Swinging movement of the blade beyond its lifting position (Fig. 3) is limited similarly to swinging movement of theblades 5.Y l v Interpo'sed between the segmental frames are segmental -panels II formed preferably of light but'rigid sheet .metal, the side edges of these panels being insertable into grooves I8 provided therefor in the. sides of the frames I3. Thus the segmental panels andthe. segmental frames at `the'ends thereof cooperate to form a ring-like vrotorlB which extends around the inner rotor.

. [The two yrotors are adapted to rotate simultane- `ou'slyinopposite directionsk respectively, and during -this rotation the depending blades carried thereby will move to the positions of Fig. 3 for the -exertion of a liftingl force. Should the rotathis figure, and from the right of Fig. 3 against the right face of blade I5 in this figure, to swing these blades with much force to frame-closing tion of the rotor'be stoppedior any reason and the rotor start to descend by gravity, or should the'rotors begin to turn in a direction opposite to .that intended `for lifting purposes the blades Aof the two rotorswill swing into positions closing the frames so that all of the blades will cooperate with the -panels ofthe rotors to form an umbrelladike' retarding element or parachute for the purpose of slowingthe descent.

.The-,swinging of theblades to frame-closing Qposition occurs vas follows: Assuming that the rotors. are being rotated in the directions of the arrows in Fig. l, the blades will be in lifting positionseen 'in all the figures. If now the rotors stop rotating, for example, as descent begins the 4panel areasof the rotors located in back of the respective blades of the rotors will form pressure areasfully4 suicient to exert pressure from the lleftiri Fig. 3 against the left face of blade 5 in position. It may be noted that in this operation there is no, or negligible, pressure on the right surface of blade 5 in Fig. 3 or the left surface of blade i5 in Fig. 3, as air escapes upwardly in front of the respective blades through the frame openlngs. l .s

Obviously the two shafts may be simultaneously rotated in opposite directions respectively by any suitable means provided for that purpose. Preferably, for example, I may provide two engines so arranged as to exert opposite torques on the cockpit.

Furthermore, instead of utilizing metal panels for filling the spaces between the segmental frames, other suitable types of llers could be used.

What is claimed is:

'In a helicopter a rotor, an upstanding shaft mounted to rotate about a vertical axis, circumferentially spaced segmental frames carried by 'the shaft for rotation therewith,.said frames having side bars which diverge as theyrecede .from the shaft, said frames extending outwardly from and inclining downwardlyas they recede from the shaft, panels carried byT and extending between the frames, and aV blade pivotally mounted on each frame for movement about lan axis which lies parallel with and adjacent thetrailing side bar of its respective frame from an ascending position in which it vengages the adjacent side bar oi its respective frame and lies at an acute angle to the adjacent trailing panel to a descending position in which it lies across and in contact with its associated frame. ..1 CHARLES 0.1SIPE.

REFERENCES CITED The following references vare ofrecordin'the file of this patent: i

UNITED STATES P.I rrn'N'rs I,

Y Date 297,268 Great Britain sept. 2o, 1928 

